Trait Monoid 

pub trait Monoid: Semigroup {
    // Required method
    fn empty() -> Self;
}

A Monoid is a Semigroup that has an empty/ zero value

Required Methods

fn empty() -> Self

For a given Monoid, returns its empty/zero value

Examples

use frunk::Monoid;

assert_eq!(<i16 as Monoid>::empty(), 0);

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety", so this trait is not object safe.

Implementations on Foreign Types

impl Monoid for f32

fn empty() -> Self

impl Monoid for f64

fn empty() -> Self

impl Monoid for i8

fn empty() -> Self

impl Monoid for i16

fn empty() -> Self

impl Monoid for i32

fn empty() -> Self

impl Monoid for i64

fn empty() -> Self

impl Monoid for isize

fn empty() -> Self

impl Monoid for u8

fn empty() -> Self

impl Monoid for u16

fn empty() -> Self

impl Monoid for u32

fn empty() -> Self

impl Monoid for u64

fn empty() -> Self

impl Monoid for usize

fn empty() -> Self

impl Monoid for String

Available on crate feature alloc only.

fn empty() -> Self

impl<A: Monoid> Monoid for (A,)

fn empty() -> Self

impl<A: Monoid, B: Monoid> Monoid for (A, B)

fn empty() -> Self

impl<A: Monoid, B: Monoid, C: Monoid> Monoid for (A, B, C)

fn empty() -> Self

impl<A: Monoid, B: Monoid, C: Monoid, D: Monoid> Monoid for (A, B, C, D)

fn empty() -> Self

impl<A: Monoid, B: Monoid, C: Monoid, D: Monoid, E: Monoid> Monoid for (A, B, C, D, E)

fn empty() -> Self

impl<A: Monoid, B: Monoid, C: Monoid, D: Monoid, E: Monoid, F: Monoid> Monoid for (A, B, C, D, E, F)

fn empty() -> Self

impl<A: Monoid, B: Monoid, C: Monoid, D: Monoid, E: Monoid, F: Monoid, G: Monoid> Monoid for (A, B, C, D, E, F, G)

fn empty() -> Self

impl<A: Monoid, B: Monoid, C: Monoid, D: Monoid, E: Monoid, F: Monoid, G: Monoid, H: Monoid> Monoid for (A, B, C, D, E, F, G, H)

fn empty() -> Self

impl<A: Monoid, B: Monoid, C: Monoid, D: Monoid, E: Monoid, F: Monoid, G: Monoid, H: Monoid, I: Monoid> Monoid for (A, B, C, D, E, F, G, H, I)

fn empty() -> Self

impl<A: Monoid, B: Monoid, C: Monoid, D: Monoid, E: Monoid, F: Monoid, G: Monoid, H: Monoid, I: Monoid, J: Monoid> Monoid for (A, B, C, D, E, F, G, H, I, J)

fn empty() -> Self

impl<A: Monoid, B: Monoid, C: Monoid, D: Monoid, E: Monoid, F: Monoid, G: Monoid, H: Monoid, I: Monoid, J: Monoid, K: Monoid> Monoid for (A, B, C, D, E, F, G, H, I, J, K)

fn empty() -> Self

impl<A: Monoid, B: Monoid, C: Monoid, D: Monoid, E: Monoid, F: Monoid, G: Monoid, H: Monoid, I: Monoid, J: Monoid, K: Monoid, L: Monoid> Monoid for (A, B, C, D, E, F, G, H, I, J, K, L)

fn empty() -> Self

impl<A: Monoid, B: Monoid, C: Monoid, D: Monoid, E: Monoid, F: Monoid, G: Monoid, H: Monoid, I: Monoid, J: Monoid, K: Monoid, L: Monoid, M: Monoid> Monoid for (A, B, C, D, E, F, G, H, I, J, K, L, M)

fn empty() -> Self

impl<A: Monoid, B: Monoid, C: Monoid, D: Monoid, E: Monoid, F: Monoid, G: Monoid, H: Monoid, I: Monoid, J: Monoid, K: Monoid, L: Monoid, M: Monoid, N: Monoid> Monoid for (A, B, C, D, E, F, G, H, I, J, K, L, M, N)

fn empty() -> Self

impl<A: Monoid, B: Monoid, C: Monoid, D: Monoid, E: Monoid, F: Monoid, G: Monoid, H: Monoid, I: Monoid, J: Monoid, K: Monoid, L: Monoid, M: Monoid, N: Monoid, O: Monoid> Monoid for (A, B, C, D, E, F, G, H, I, J, K, L, M, N, O)

fn empty() -> Self

impl<A: Monoid, B: Monoid, C: Monoid, D: Monoid, E: Monoid, F: Monoid, G: Monoid, H: Monoid, I: Monoid, J: Monoid, K: Monoid, L: Monoid, M: Monoid, N: Monoid, O: Monoid, P: Monoid> Monoid for (A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P)

fn empty() -> Self

impl<A: Monoid, B: Monoid, C: Monoid, D: Monoid, E: Monoid, F: Monoid, G: Monoid, H: Monoid, I: Monoid, J: Monoid, K: Monoid, L: Monoid, M: Monoid, N: Monoid, O: Monoid, P: Monoid, Q: Monoid> Monoid for (A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q)

fn empty() -> Self

impl<A: Monoid, B: Monoid, C: Monoid, D: Monoid, E: Monoid, F: Monoid, G: Monoid, H: Monoid, I: Monoid, J: Monoid, K: Monoid, L: Monoid, M: Monoid, N: Monoid, O: Monoid, P: Monoid, Q: Monoid, R: Monoid> Monoid for (A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R)

fn empty() -> Self

impl<A: Monoid, B: Monoid, C: Monoid, D: Monoid, E: Monoid, F: Monoid, G: Monoid, H: Monoid, I: Monoid, J: Monoid, K: Monoid, L: Monoid, M: Monoid, N: Monoid, O: Monoid, P: Monoid, Q: Monoid, R: Monoid, S: Monoid> Monoid for (A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S)

fn empty() -> Self

impl<A: Monoid, B: Monoid, C: Monoid, D: Monoid, E: Monoid, F: Monoid, G: Monoid, H: Monoid, I: Monoid, J: Monoid, K: Monoid, L: Monoid, M: Monoid, N: Monoid, O: Monoid, P: Monoid, Q: Monoid, R: Monoid, S: Monoid, T: Monoid> Monoid for (A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T)

fn empty() -> Self

impl<A: Monoid, B: Monoid, C: Monoid, D: Monoid, E: Monoid, F: Monoid, G: Monoid, H: Monoid, I: Monoid, J: Monoid, K: Monoid, L: Monoid, M: Monoid, N: Monoid, O: Monoid, P: Monoid, Q: Monoid, R: Monoid, S: Monoid, T: Monoid, U: Monoid> Monoid for (A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U)

fn empty() -> Self

impl<T> Monoid for Option<T>

where T: Semigroup + Clone,

fn empty() -> Self

impl<T> Monoid for Vec<T>

where T: Clone,

Available on crate feature alloc only.

fn empty() -> Self

Implementors

impl Monoid for All<bool>

impl Monoid for All<i8>

impl Monoid for All<i16>

impl Monoid for All<i32>

impl Monoid for All<i64>

impl Monoid for All<isize>

impl Monoid for All<u8>

impl Monoid for All<u16>

impl Monoid for All<u32>

impl Monoid for All<u64>

impl Monoid for All<usize>

impl Monoid for Any<bool>

impl Monoid for Any<i8>

impl Monoid for Any<i16>

impl Monoid for Any<i32>

impl Monoid for Any<i64>

impl Monoid for Any<isize>

impl Monoid for Any<u8>

impl Monoid for Any<u16>

impl Monoid for Any<u32>

impl Monoid for Any<u64>

impl Monoid for Any<usize>

impl Monoid for Product<f32>

impl Monoid for Product<f64>

impl Monoid for Product<i8>

impl Monoid for Product<i16>

impl Monoid for Product<i32>

impl Monoid for Product<i64>

impl Monoid for Product<isize>

impl Monoid for Product<u8>

impl Monoid for Product<u16>

impl Monoid for Product<u32>

impl Monoid for Product<u64>

impl Monoid for Product<usize>